The car will make its appearance at the Geneva motor show in March next month

Volkswagen has confirmed its XL1 hybrid for production, which will make its appearance at the Geneva motor show next month.

The two-seat Volkswagen XL1 has a plug-in diesel hybrid system that allows it to achieve 314 MPG and 31 miles on electric power alone. The CO2 emissions sits at 21 g/km, and it is considered the most aerodynamic car with a Cd figure of 0.189. It's also very light at just 1,752 pounds.

The XL1 hybrid features a 47 bhp 0.8-litre, two-cylinder diesel engine with a 27 bhp electric motor and 5.5 kWh battery pack. According to VW, the XL1 can go from 0-62 MPH in 12.7 seconds with a top speed of 98 MPH.

The XL1 also has some other interesting features, such as a design that completely covers the rear wheels to reduce drag; a pair of rear-facing mirrors on the side of the car instead of door mirrors; wing doors that swivel upwards and forwards, and slightly offset seats for the most interior space possible.

As mentioned, the XL1 is very light at just 1,752 pounds because it is mainly made of carbon monocoque. Aluminum is used on the suspension and dampers as well as ceramic for the brakes and magnesium wheels.

A price has not been confirmed yet, but some reports say the XL1 could cost as much as £70,000 ($107,000 USD). The car will make its appearance at the Geneva motor show in March next month.

To add another point, I love how these mega MPG claims completely neglect the cost of electricity, which is how they are achieving such high numbers.

In theory with no inefficiency, a typical designed sedan, with Cd around .3 and normal frontal area, could only achieve ~140mpg @ 60mph under typical sea level atmospheric conditions. That's it. There's X amount of energy in 1 gallon of gasoline and it takes X amount of energy to move that car against the wind resistance and rolling resistance of tires at that speed. That's also assuming you can convert 100% of gasoline's energy into motion, which right now runs closer to 20-25%. So using the engine and driveline inefficiency, we are closer to 30-40mpg highway as a theoretical top limit for a typical sedan. In reality, car's today aren't that far off.

This is simplified, and of course ignores weight that affects rolling resistance, and the additional energy required to overcome changes in momentum (eg, stop and go, City MPG). A gallon of Diesel contains more energy, and hence would boost those calculations slightly.

To improve this, you need to lower the Coefficient of drag (Cd), significantly reduce the cross sectional area, improve the tires (but improved rolling resistance means less traction.....not quite a good tradeoff) and of course improve engine efficiency. Or go the hybrid route which stores energy in another form.

You can't create energy out of the blue, but you can store it for later use. In this case, the electric batteries. But that doesn't come for free, so it needs to be calculated and provided in these MPG Equivalent claims.